Air cleaner filter assembly for motor vehicles operating in extreme weather conditions

ABSTRACT

A filter assembly for a motor-vehicle air cleaner comprises a main filter, an auxiliary filter set apart from the main filter, and a filter mount fixed to and configured to support the main filter and the auxiliary filter. In this embodiment, the filter mount is fittable in and removable from a housing of the air cleaner, and comprises a sealing element passing between the main filter and the auxiliary filter.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to U.S. Provisional Application61/230,522, filed on Jul. 31, 2009 and entitled FRESH AIR SUPPLY FORMOTOR VEHICLES OPERATING IN EXTREME WEATHER CONDITIONS, the entirety ofwhich is hereby incorporated by reference herein for all purposes.

TECHNICAL FIELD

The present application relates to the field of motor vehicleengineering, and more particularly, to providing adequate air flow to amotor-vehicle engine system under conditions of heavy snow or dust.

BACKGROUND AND SUMMARY

The internal combustion engine of a motor vehicle requires an adequatesupply of filtered, fresh air. Accordingly, air from the atmosphere maybe drawn through a particle filter to remove dust and other particulatesen route to the engine intake. Under normal operating conditions of themotor vehicle—normal weather, a normal operating environment, etc., asingle particle filter may provide many months of trouble-free airfiltration before a replacement is needed. During extreme weatherconditions, however, the filter may clog prematurely, therebyrestricting air flow into the engine and degrading motor-vehicleperformance. Such extreme weather conditions may include very snowy ordusty conditions, for example.

One solution to the problem noted above is to install a specializedgrille cover on the motor vehicle to prevent entry of snow and/or dustinto the engine compartment. However, such a grille cover may beexpensive and must be matched particularly to the front-endconfiguration of the motor vehicle on which it is installed. Further,the motor-vehicle operator may be obliged to install and remove thegrille cover repeatedly, in response to changing weather conditions,causing dissatisfaction. The inventors herein have recognized theselimitations and have devised an alternative, or additional, approachaimed at providing fresh air to the engine of a motor vehicle operatingin extreme weather conditions.

Therefore, one embodiment provides a filter assembly for a motor-vehicleair cleaner, the air cleaner adapted to provide clean intake air. Thefilter assembly comprises a main filter, an auxiliary filter set apartfrom the main filter, and a filter mount fixed to and configured tosupport the main filter and the auxiliary filter. In this embodiment,the filter mount is fittable in and removable from a housing of the aircleaner, and comprises a sealing element passing between the main filterand the auxiliary filter. Such an approach may be used with, or without,specialized grille covers or other such devices

It will be understood that the summary above is provided to introduce insimplified form a selection of concepts that are further described inthe detailed description, which follows. It is not meant to identify keyor essential features of the claimed subject matter, the scope of whichis defined by the claims that follow the detailed description. Further,the claimed subject matter is not limited to implementations that solveany disadvantages noted above or in any part of this disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 schematically shows aspects of a system for providing cleanintake air to a motor-vehicle engine during snowy or dusty conditions,in accordance with an embodiment of the present disclosure.

FIG. 2 schematically shows a filter assembly for a motor-vehicle aircleaner in accordance with an embodiment of the present disclosure.

FIGS. 3-5 show a series of views of a filter assembly for amotor-vehicle air cleaner in accordance with an embodiment of thepresent disclosure.

FIG. 6 shows a perspective view of a housing body of a motor-vehicle aircleaner in accordance with an embodiment of the present disclosure.

FIG. 7 shows a perspective view of a flow restrictor of a motor-vehicleair cleaner in accordance with an embodiment of the present disclosure.

FIG. 8 shows a perspective view of a retaining band of a motor-vehicleair cleaner in accordance with an embodiment of the present disclosure.

FIG. 9 shows a perspective view of a motor-vehicle air cleaner inaccordance with an embodiment of the present disclosure.

FIG. 10 shows a cross-sectional view of a motor-vehicle air cleaner inaccordance with an embodiment of the present disclosure.

FIG. 11 shows an air-cleaner installed in an engine compartment of amotor vehicle in accordance with an embodiment of the presentdisclosure.

FIG. 12 shows an exploded view of the air-cleaner of FIG. 11 inaccordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION

The subject matter of the present disclosure is now described by way ofexample and with reference to certain illustrated embodiments.Components that may be substantially the same in one or more embodimentsare identified coordinately and are described with minimal repetition.It will be noted, however, that components identified coordinately indifferent embodiments of the present disclosure may be at least partlydifferent. It will be noted that some of the figures included in thisdisclosure are schematic, and are identified as such. In the schematicfigures, views of the illustrated embodiments are generally not drawn toscale; aspect ratios, feature size, and numbers of features may bepurposely distorted to make selected features or relationships easier tosee. Other figures included in this disclosure are based on photographicimages or computer models of the various embodiments. The figuresidentified as such are rendered to scale.

FIG. 1 schematically shows aspects of an example system 10 for providingclean intake air to a motor-vehicle engine. The illustrated system isspecially configured to resist clogging and to provide the intake airduring snowy or dusty conditions, but may be used during normal ambientconditions as well. Further, the system may be used in virtually anymotor-vehicle application where reduced flow restriction, increasedfilter capacity, and reduced noise/vibration in the air intake systemare desired.

System 10 includes engine 12, in which combustion chambers 14 arecoupled to intake manifold 16 and to exhaust manifold 18. In thecombustion chambers, combustion may be initiated and sustained via sparkignition and/or compression ignition in any variant. The engine may beconfigured to consume any of a variety of fuels: gasoline, alcohols,diesel, biodiesel, compressed natural gas, hydrogen, etc. The fuel maybe supplied to the combustion chambers via direct injection, portinjection, or any combination thereof.

System 10 is configured to supply air to engine 12. Air enters thesystem via air cleaner 20 and flows through various downstreamair-handling components before entering intake manifold 16. Suchcomponents (not shown in the drawings) may include a compressor, acharge-air intercooler, and/or a throttle, for example. Engine exhaustreleased from exhaust manifold 18 may flow through various downstreamexhaust-system components before entering exhaust conduit 22. Suchcomponents (not shown in the drawings) may include one or moreexhaust-aftertreatment devices—nitrogen-oxide reducing catalysts,hydrocarbon-oxidizing catalysts, soot filters, and the like. Fromexhaust conduit 22, the engine exhaust may flow to other exhaust-systemcomponents—one or more additional exhaust-aftertreatment devices, asilencer, etc.—before being discharged to the atmosphere.

Air cleaner 20 is adapted to provide clean intake air during snowy ordusty conditions. The air cleaner includes filter assembly 24, shown ingreater detail in FIG. 2. The filter assembly may include two or moresuitably supported filters, e.g., a main filter and an auxiliary filterset apart from each other. Accordingly, FIGS. 1 and 2 show filter mount26 coupled to main filter 28 and auxiliary filter 30. The filter mountis fixed to and configured to support the main filter and the auxiliaryfilter while allowing air to flow through the filters. In the embodimentshown in FIGS. 1 and 2, the filter mount has an open, frame-likestructure from which the main and auxiliary filters are suspended fromabove. The main and auxiliary filters may be coupled to the filter mountby molding the filter mount around the filters, or with the aid of anadhesive, or in any other suitable manner. In the illustratedembodiment, the filter mount frames two open areas: a first open arealocated over the main filter and a second open area located over theauxiliary filter. The open areas allow air to pass through the filtermount. In other embodiments, there may be more than two filters, andfilter mount may frame more than two open areas.

Main filter 28 and auxiliary filter 30 may be substantially the same orat least partly different. In the embodiment shown in FIGS. 1 and 2, themain and auxiliary filters are both pleat-pack filters, but the mainfilter is taller and longer than the auxiliary filter. In otherembodiments, other kinds of filters may be used. Further, the mainfilter may be longer than, wider than, and/or taller than the auxiliaryfilter in the various embodiments of the present disclosure. In oneembodiment, the main filter may be 90 millimeters in height, and theauxiliary filter may be 50 millimeters in height.

In the embodiment shown in FIG. 1, a significant pressure differentialmay develop across filter assembly 24 when engine 12 is running.Specifically, the inlet side of the filter assembly may experiencebarometric pressure, while the outlet side may experience manifold orturbocharger-inlet vacuum. During conditions when main filter 28 isclogged with snow or dust, the pressure differential may be greaterstill as a result of decreased air flow. Therefore, to minimize the riskthat unbalanced stresses may deform the pleat packs of the main and/orauxiliary filters, the filter assembly may include a rigid mesh disposedbetween the main and auxiliary filters and the filter mount, andextending at least over the open areas thereof. Accordingly FIG. 2 showsrigid mesh 50 arranged in this manner. For added stability, the rigidmesh may be embossed to form a ridge projecting opposite the main andauxiliary filters, and the ridge may be inserted in a receiving nook ofthe filter mount. FIG. 1 provides a cross-sectional view of thisfeature, with rigid mesh 50 inserted in receiving nook 52. In someembodiments, the main and/or auxiliary filter may be further reinforcedby applying one or more adhesive strips to the side opposite the rigidmesh.

FIGS. 3-5 show a series of views of filter assembly 24 in anotherembodiment. The dimensions of the filter assembly shown in thesedrawings are accurate to the scale of the embodiment. FIG. 3 showsfilter mount 26, main filter 28, auxiliary filter 30, and sealing groove42. FIGS. 4 and 5 show close-up views of sealing groove 42, rigid mesh50, and receiving nook 52.

Returning now to FIG. 1, air cleaner 20 includes an air-cleaner housingconfigured to fittably and removably accommodate the filter assembly andto enclose the main filter and the auxiliary filter separately when thefilter assembly is accommodated therein. In the illustrated embodiment,the air-cleaner housing comprises housing body 32 and a housing cover34. The housing body may be any suitable structure configured to housemain filter 28, auxiliary filter 30, and other air cleaner components,as indicated below. Further, the housing body is configured to admit airto the main and auxiliary filters. Accordingly, the housing body mayhave at least a partly open structure, with ribbing provided in at leastsome of the remaining closed, solid areas for added mechanical strength.

Housing cover 34 may be sealably coupled to at least one of the housingbody and the filter assembly, and configured to receive air flow fromthe main filter and the auxiliary filter. In the embodiment shown inFIG. 1, the housing cover is sealably coupled to the housing body and tofilter mount 26. The housing cover may be secured to the housing body inany suitable manner—via a series of two-part clamps arranged in registryaround the peripheries of the housing body and housing cover, forexample. The housing cover is fluidically coupled to intake manifold 16via suitable air-handling components. As a result, the air spaceenclosed by the filter assembly and the housing cover may, when theengine is running, be maintained at the partial vacuum of the intakemanifold or turbocharger inlet. Accordingly, atmospheric air from theinterior of the housing body is drawn through the main and auxiliaryfilters and into the air space enclosed by the filter assembly and thehousing cover.

Filter mount 26 is configured to sealably couple to housing body 32. Forexample, the edge of the filter mount may rest on a receiving flangeconstructed in the housing body. Resilient materials on the receivingflange and/or the filter mount may provide a tight seal between theseparts when the filter mount is compressed against the housing body—viahousing cover 34, for example.

In the various embodiments of the present disclosure, air cleaner 20 maybe configured to substantially prevent air flow between main filter 28and auxiliary filter 30. To this end, filter assembly 24 may comprise afirst sealing element, and the air-cleaner housing may comprise a secondsealing element, complementary to the first sealing element. The firstand second sealing elements may form a seal passing between the mainfilter and the auxiliary filter. Accordingly, in the embodiment shown inFIG. 1, housing body 32 includes dividing wall 36, which divides the airspace inside the housing body into a main compartment 38 surrounding themain filter and an auxiliary compartment 40 surrounding the auxiliaryfilter. Filter mount 26 includes sealing groove 42, which is positionedbetween the main filter and the auxiliary filter and configured toreceive and sealably couple to the dividing wall. In one embodiment, thesealing groove comprises a resilient material (e.g., a polyurethane) andis appropriately sized so that receipt of the dividing wall in thesealing groove forms a substantially air-tight seal dividing the mainfilter from the auxiliary filter. In the illustrated embodiment, thesealing element extends from one edge of the filter mount to theopposite edge of the filter mount, i.e., across an entire width of thefilter mount. In one embodiment, the sealing groove may be 13millimeters in width and 13 millimeters in height.

FIG. 6 shows a perspective view of housing body 32 in anotherembodiment. The dimensions of the housing body shown in FIG. 6 are basedon a model of this embodiment and are drawn to scale. The drawing showsdividing wall 36 separating main compartment 38 from auxiliarycompartment 40.

In the various embodiments of the present disclosure, certain designfeatures are enabled by enclosing main filter 28 and auxiliary filter 30in separate compartments of air cleaner 20. In particular, the aircleaner may be configured to provide different amounts of flowrestriction to the two respective filters. In the embodimentsillustrated herein, the frame-like structure of the air filter housingmay provide little flow restriction per se to either filter. However,the air filter housing may accommodate additional components thatprovide a significant flow restriction to one filter or the other.Accordingly, FIG. 1 shows flow restrictor 44 disposed below and influidic communication with the auxiliary filter on the inlet side, i.e.,inside housing body 32. The flow restrictor is configured to partlyrestrict air flow to the auxiliary filter.

Flow restrictor 44 may be sized and shaped to fit the interior ofhousing body 32 directly below auxiliary filter 30. The flow restrictormay provide enough restriction to cause the great majority of intake airto flow through the main filter instead of the auxiliary filter as longas the main filter is substantially unclogged. However, the restrictionmay be small enough so that when the main filter is clogged, as couldoccur during extreme weather conditions, air flow is drawn through theauxiliary filter. The air flow may be sufficient to support combustionin the engine, e.g., to prevent the engine from stalling.

Because auxiliary filter 30 does not receive a significant air flowunless or until main filter 28 becomes clogged, it is unlikely for theauxiliary filter to accumulate a clogging layer of snow and/or dust,even under conditions where snow and/or dust accumulate on and clog themain air filter.

In some embodiments, flow restrictor 44 may include a plurality ofmacro-scale features—orifices, obstructions, screens, vanes, wadding,etc.—that restrict the air flow. In other embodiments, theflow-restricting features may be much smaller in size. For example, theflow restrictor may comprise an open-cell flow-restricting foam, indiscrete, attached or unattached monoliths or as a single monolith. Thepore density of the foam may range from below 40 to above 100 pores perinch (ppi). In one embodiment, the pore density of the foam may bebetween 40 and 100 ppi, inclusively. In embodiments where absorption ofwater into the flow restrictor is to be particularly avoided, foamhaving a pore density of 80 ppi may be used.

In the embodiment illustrated in FIG. 1, flow restrictor 44 comprises aresilient polyurethane foam monolith. The resiliency of the foamadvantageously allows the flow restrictor to be inserted into apre-formed cavity in the air-cleaner housing and be retained there by asealing flange. Accordingly, housing body 32 comprises sealing flange46, which frames an open region configured to allow air to flow toauxiliary filter 30. The sealing flange is configured to prevent dustand snow from migrating above the flow restrictor, e.g., between theflow restrictor and auxiliary filter 30. In one embodiment, the sealingflange may be 4 millimeters thick and 12 millimeters wide. The resilientflow restrictor is inserted into the opening and retained there by thesealing flange. In one embodiment, the flow restrictor may have a grooveformed therein for receiving the sealing flange. The groove may have anysuitable shape and dimensions; for example, the groove may be 3millimeters wide and between 10 and 12 millimeters deep. In suchembodiments, interference between the sealing flange and the groove mayhelp to keep the flow restrictor in place despite motor-vehiclevibrations, dimensional changes over time, etc. In one example, onemillimeter of interference created by the thickness of the sealingflange may be used.

FIG. 7 shows a perspective view of flow restrictor 44 in anotherembodiment. The dimensions of the flow restrictor shown in FIG. 7 arebased on a model of this embodiment and are drawn to scale.

In some embodiments, additional measures may be taken to ensure thatflow restrictor 44 remains firmly seated in the air-cleaner housing. Forexample, air cleaner 20 may comprise one or more bands extending fromone locus of the housing body to another locus of the housing body, andconfigured to retain the flow restrictor in its place. Accordingly, theembodiment shown in FIG. 1 includes retaining band 48 spanning an openarea of housing body 32 behind which the flow restrictor is situated.

FIG. 8 shows a perspective view of retaining band 48 in anotherembodiment. The dimensions the retaining band shown in FIG. 8 are basedon a model of this embodiment and are drawn to scale.

Returning again to FIG. 1, housing body 32 may, in some embodiments, beheated in the vicinity of flow restrictor 44. Heating the housing bodyoffers an advantage in scenarios where even the auxiliary filter may besubject to an accumulation of snow. Accordingly, heating the housingbody may prevent at least the auxiliary filter from being clogged withsnow, thereby providing adequate air flow to the engine. In oneembodiment, the housing body may be heated electrically. However,numerous embodiments are contemplated wherein the housing body is heatedvia exhaust gas, either directly or indirectly. In the embodiment shownin FIG. 1, for example, the housing body is supplied heat via exhaustconduit 22, which may be adapted to run through or around the housingbody. In other embodiments, the housing body may be supplied heat via aheat pipe or other heat exchanger configured to draw heat from theexhaust conduit. In embodiments where the air-cleaner housing is heated,the various constituents of the air cleaner, including the flowrestrictor, may comprise a heat-resistant material.

In other embodiments, where air cleaner 20 is not actively heated, othermeasures may be taken to prevent or mitigate the accumulation of snow,especially in the vicinity of auxiliary filter 30. In the embodimentshown in FIG. 1, for example, housing body 32 has an elongated shape inthe vicinity of flow restrictor 44. The elongated shape may encouragesnow to slide off, rather than accumulate on, the air-cleaner housing.

FIGS. 9 and 10 show, respectively, a perspective view and across-sectional view of air cleaner 20 in another embodiment. Thedimensions of the air cleaner shown in these drawings are based on amodel of the embodiment and are drawn to scale. The perspective viewshows housing body 32, housing cover 34, flow restrictor 44, andretaining band 48. The cross-sectional view further shows filter mount26, main filter 28, auxiliary filter 30, main compartment 38, and massair-flow sensor 54.

FIG. 11 shows air-cleaner 20 installed in the engine compartment of amotor vehicle 56 from an above perspective. FIG. 12 shows an explodedview of the air cleaner, which includes filter assembly 24, housing body32, housing cover 34, flow restrictor 44, and retaining band 48. FIG. 12also shows air inlet 58, clean-air conduit 60, and bracket 62. Thebracket may be any suitable bracket configured to at least partly securethe air cleaner within the engine compartment.

Finally, it will be understood that the articles, systems and methodsdescribed herein are exemplary in nature, and that these specificembodiments or examples are not to be considered in a limiting sense,because numerous variations are contemplated. Accordingly, the presentdisclosure includes all novel and non-obvious combinations andsub-combinations of the various systems and methods disclosed herein, aswell as any and all equivalents thereof.

1. A filter assembly for an air cleaner configured to provide cleanintake air for a motor vehicle, the filter assembly comprising: a mainfilter; an auxiliary filter set apart from the main filter; and a filtermount fixed to and configured to support the main filter and theauxiliary filter, the filter mount fittable in and removable from ahousing of the air cleaner, and comprising a first sealing elementpassing between the main filter and the auxiliary filter.
 2. The filterassembly of claim 1, where the first sealing element is configured toreceive a complementary second sealing element formed in the housing. 3.The filter assembly of claim 1, where the first sealing element extendsfrom one edge of the filter mount to an opposite edge of the filtermount.
 4. The filter assembly of claim 1, where the first sealingelement extends across an entire width of the filter mount.
 5. Thefilter assembly of claim 1, where the first sealing element comprises agroove.
 6. The filter assembly of claim 5, where the groove isconfigured to receive a dividing wall of the housing.
 7. The filterassembly of claim 6, where receipt of the dividing wall in the grooveforms a substantially air-tight seal dividing the main filter from theauxiliary filter.
 8. The filter assembly of claim 2, where one or moreof the first sealing element and the second sealing element comprises aresilient material.
 9. The filter assembly of claim 8, where theresilient material comprises a polyurethane.
 10. The filter assembly ofclaim 1, where one or more of the main filter and the auxiliary filtercomprises a pleat-pack filter.
 11. The filter assembly of claim 1, wherethe main filter is one or more of longer, wider, and taller than theauxiliary filter.
 12. A filter assembly for a motor-vehicle air cleaner,the air cleaner adapted to provide clean intake air, the filter assemblycomprising: a main filter; an auxiliary filter set apart from the mainfilter; and a filter mount framing first and second open areas andconfigured to support the main filter below the first open area and theauxiliary filter below the second open area, the filter mount fittablein and removable from a housing of the air cleaner, and comprising afirst sealing element passing between the main filter and the auxiliaryfilter.
 13. The filter assembly of claim 12, further comprising a rigidmesh disposed between the main and auxiliary filters and the filtermount, and extending at least over the first and second open areas. 14.The filter assembly of claim 13, where the rigid mesh is embossed toform a ridge projecting opposite the main and auxiliary filters, andwhere the ridge is inserted in a receiving nook of the filter mount. 15.The filter assembly of claim 12, wherein the main filter spans the firstopen area from below the filter mount, and the auxiliary filter spansthe second open area from below the filter mount.
 16. A filter assemblyfor a motor-vehicle air cleaner, the air cleaner adapted to provideclean intake air, the filter assembly comprising: a main filter; anauxiliary filter set apart from the main filter; and a filter mountframing first and second open areas and configured to support the mainfilter below the first open area and the auxiliary filter below thesecond open area, the filter mount fittable in and removable from ahousing of the air cleaner, and comprising a groove passing between themain filter and the auxiliary filter and extending across an entirewidth of the filter mount.
 17. The filter assembly of claim 16, wherethe groove is configured to receive a dividing wall of the housing. 18.The filter assembly of claim 17, where receipt of the dividing wall inthe groove forms a substantially air-tight seal dividing the main filterfrom the auxiliary filter.
 19. The filter assembly of claim 17, whereone or more of the groove and the dividing wall comprises a resilientmaterial.
 20. The filter assembly of claim 16, where the main filter isone or more of longer, wider, and taller than the auxiliary filter.